48.  A 28 year old woman presents to the ER with severe lowe…

48.  A 28 year old woman presents to the ER with severe lower abdominal pain, vaginal spotting, and dizziness. She reports that her last menstrual period was 7 weeks ago. Her blood pressure is 88/54, heart rate 122 bpm, and a pregnancy test is positive. Which finding is most concerning for a ruptured ectopic pregnancy?